JPH02705Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to an improvement of a portable direction finder.

[Conventional technology]

As a portable direction finder, one in which a non-magnetic lid is provided on the receiver casing and a loop antenna is placed on the lid is disclosed in Publication of Utility Model Publication No. 28-9307, etc. A shielded loop antenna is disclosed in Japanese Utility Model Publication No. 43-27094.

[The problem that the idea aims to solve]

With such a portable direction finder, it is possible to get close to the source of weak radio waves and confirm the location of the source.

However, if the emission source is illegal radio waves, it is necessary to approach the target without being noticed.

In addition to the above-mentioned illegal radio waves, if you can only use one hand for work due to the location being detected being dangerous, it would be convenient to be able to detect while carrying it with one hand.

There is a problem in that it is desired to provide a direction finder suitable for such uses.

[Means to solve the problem]

This idea incorporates a loop antenna and a receiver inside a bag-like case, and the receiver has an output meter for monitoring the power of the amplified radio waves or a device for listening to the voices and signals contained in the radio waves. This radio wave direction finder is equipped with a monitoring section using an output terminal, and consists of a case and a cover made of insulating material, and a bag-like case with a small window for the above-mentioned monitoring section in the upper part of the case. The inside of the case is made of a conductive material, with spaces provided in at least the front and rear parts and the lower part, and the remaining part is arranged to enclose the receiver, and the above-mentioned monitoring part is provided in the upper part. The above problem can be solved by providing a direction finder having a cabinet and a shielded loop antenna placed in the space.

〔Example〕

Examples will be described below with reference to figures.

In the figure, a case 1 is provided with a cover 2, which is formed as a type of handbag usually called an attache case, that is, a bag-like case, and is made of electrically insulating material such as plastic or paper. Although not shown, except for parts that absolutely require metal, such as the lock, they are made using an insulating material that has low moisture absorption.

The case 1, cover 2, and handle 3 have the same structure as a normal handbag.

In this invention, when referring to the front and back and top and bottom positions, it refers to the position when the case 1 is held up by hand with the handle 3, that is, when the longitudinal direction of the case 1 is the front and back direction. Therefore, the left-right direction in the figure corresponds to the front-back direction.

The antenna conductor 4 is surrounded by shields 41 and 42 of the antenna, but is electrically insulated, and is arranged along the inner surface of each front, top, and bottom surface of the case 1, forming a so-called shielded loop. The shields 41 and 42 are separated as shown in the figure to prevent the electric power induced in the antenna conductor 4 from being short-circuited by the shields 41 and 42.

Therefore, it is possible to connect the shields 41 and 42 with an insulating material or to fix them to the case 1 for reinforcement.
As shown in the figure, the antenna introduction parts 51 and 52
Then, it is connected to the conductive material cabinet 6,
Only the antenna conductor 4 is introduced inside the cabinet 6.

Although not shown, a radio wave receiver is housed inside the cabinet 6, and the power of the radio waves induced in the antenna conductor 4 is applied to the receiver and amplified.

The main tuning dial 71, sub-tuning dial 72, and knobs 8 such as switches have the function of adjusting the frequency of the receiver to radio waves and adjusting the operation.By operating these, the antenna conductor 4 Amplify the power of the radio waves induced by the wave to the required amount.

The output meter 9 and the output terminal 10 are a mechanism for monitoring the amplified power, that is, a monitoring part, and the output meter 9 is connected to the antenna conductor 4.
The output terminal 10 is used to listen to sounds and signals contained in radio waves. Further, the battery 11 supplies power for operating the above-mentioned receiver and the like.

Although not shown, the case 1 is provided with a small window for adjusting and monitoring the tuning dial 72, output meter 9, etc. arranged in the upper part of the cabinet 6.

In order to improve the reception sensitivity of radio waves, it is necessary to make the cabinet 6 as small as possible, and to improve the direction detection accuracy, it is necessary to prevent the penetration of radio waves from sources other than the antenna conductor 4. As shown in FIG.
The large shields 41 and 42 are connected to the cabinet 6 through antenna introduction parts 51 and 52.

According to the above configuration, the arriving radio waves are
Since the electric wave power is induced only in the antenna conductor 4 without almost entering the cabinet 6, it can operate as a portable radio wave direction finder using a loop antenna.

Therefore, while receiving radio waves and monitoring the output of the receiver using the output meter 9 or the output terminal 10, when the handle 3 is lowered by hand and rotated,
Since the directivity pattern is shaped like a figure 8, it is possible to detect the angle of minimum sensitivity, and this angle almost coincides with the direction of arrival of the radio waves.

[Effect of idea]

According to this invention, as mentioned above, the direction finder has a loop antenna and a receiver cabinet inside the bag-like case, and the external appearance is a bag-like case similar to an attaché case, which can be lowered by hand. Since the output of the receiver can be monitored using the output meter 9 or the output terminal 10, when detecting the source of illegal radio waves, the detection work can be done without being noticed by the other party. It is possible to provide a portable direction finder that has the feature that it can be carried with one hand for detection work when only one hand is available.

[Brief explanation of the drawing]

The drawing shows an embodiment, and is a perspective view of a bag-shaped case portion shown in a transparent manner using a chain line. 1... Case, 2... Cover, 3... Hanging hand,
4...Antenna conductor, 6...Cabinet, 8...
...Knob, 9...Output meter, 10...Output terminal, 11...Battery, 41, 42...Shield, 51, 52...Introduction section, 71...Main tuning dial, 72...Sub-tuning dial.

Claims (1)

[Claims for Utility Model Registration] A bag-like case has a loop antenna and a receiver built in, and the receiver has an output meter for monitoring the power of the amplified radio waves, or a voice signal included in the radio waves. A radio wave direction finder equipped with a monitoring section using an output terminal for listening to signals, which comprises: (a) a case and a cover made of insulating material, and a small window for the monitoring section is provided in the upper part of the case; a bag-like case; b. A space is provided inside the case at least in the front and rear portions and a lower portion, the remaining portion is arranged to enclose the receiver, and the monitoring portion is provided in the upper portion; A direction finder comprising: a cabinet made of a conductive material; and c) a shielded loop antenna disposed in the space.